Well reamer



N0 3G, 1937. C. J. MAI-IER 2,191,007

WELT4J REAMER Filed Nov. 9, 1954 I /0 I I I @2f/orgy Patented Nov. 30, 1937 UNITED STATES PATENT OFFICE 13 Claims.

of the well bore, the cutting edges of said parts travelling in a path partially bounding or dening a sphere whose axis is in the axis of rotation of the reamer shank. The cutting parts having their active edges travelling, i'n a spherical plane or course have active cutting engagement with the wall of the'well bore at spaced points throughout its circumference to make the bore smooth and ream it to a uniform full gauge.

Another object of the invention is to provide a well reamer including an annular cutter sur? rounding the reamer shank and a novel and particularly eiective anti-friction retaining means mounting the cutter on an axis inclined with re- 5 spect to the axis of roi-.ation of the shank; whereby the shank and cutter are related for relative rotation.

Another object of the invention is to provide a well reamer embodying a cutter in the form of a collar or tubular part of considerable longitudinal extent surrounding the reamer shank at anangle thereto and the shank and cutter being related for relative rotation.

Another object of the invention is to provide a well reamer of the' character mentioned in which the gyratory cutter has novel teeth or cutting parts which have a clawing 'or digging action in engaging the formation at the wall of the well bore.

Another object of the invention is to provide a well reamer of the character mentioned in Vwhich the cutter may be easily and quickly arranged on and removed from the shank without disconnecting parts of the shank whereby the shank may be a simple, integral part or member.

A further object of the invention is to provide an improved well reamer embodying a minimum number of simple, sturdyg inexpensive parts;

50 The various objects and features of my invention will be fully understood from the following detailed description of a typical form and appli- ,cation ofthe invention, throughoutv which description reference is made to the accompanying drawing, in which:

(Cl. Z55-73) Fig. 1 is a side elevation of the reamer provided by this invention. Fig. 2 is a View similar to Fig.

1 illustratingthe lower portion of the shank and the cutter andits mounting in central longitudinal cross section. Fig. 3 is a transverse detailed 6 sectional view taken substantially as indicated by line 3-3 on Fig. 1. Fig. 4 is an enlarged fragmentary detailed sectional View of a portion of the shank and a portion of the cutter illustrating the cutter mounting and retaining means. Fig. 5 isa viewv similar to Fig. 4 illustrating a slightly modied'form of cutter tooth.

The reamer of the present invention includes, generally, a body or shank I0 adapted to be connected or interposed in a drilling string, a cutter II surrounding the shank I0 and disposed atan angle thereto, and means I2 rotatably mounting and-retaining the cutter I I on the shank III.

'I'he body or shank I0 constitutes a carrier or support for the cutter II and-is adapted to be connected in a drilling stem or drilling string to form a part thereof. In accordance with the invention the shank I0 may be a simple integral elongate member as illustrated in the drawing. The shank II) is provided at its opposite ends with means for facilitating its connection in the drilling string. In the case illustrated inthe drawing a tapered screw-threaded pin I3 is provided on the upper end of the shank and a tapered socket il is provided in the lower end of the shank for connecting it in the well drilling string. A central longitudinal fluid passage I5 extends longitudinally through the shank I0 from one end to the other to pass or conduct the circulation uid usually employed in the rotary method of well drilling. 4

The shank I0 is provided with a bearing or collar portion I6 for 'carrying or supporting the cutter II. The portion I6 is suitably spaced between the ends of the shank l0 and preferably .40 of substantial diameter. The cutter carryingw'" shank portion I6 is generally cylindrical and its central longitudinal axis A is inclined with respect to the longitudinal axis B of the shank. It is preferred to` have -a downwardly facing thrust shoulder at the upper end of the cutter supporting portion I6. With the portion I6 pitched or inclined as described above a downwardly facing shoulder I'I occurs at the upper end of the portion at one side of the shank I0.,50 The opposite side of 'the shank |0- may be unda ened or provided with a `flange I8 whose lower end*k forms 'a continuation of lthe shoulder I1. The thrust shoulder Il is thus continuous or annular and is preferably normal to the inclined axis A.

An enlargement4 29 may be provided on the shank IIJ where the lower end of theportion I6 extends outwardly beyond the major portion of the shank. The enlargement 20 is preferably provided with a substantially spherically curved surface which joins the cylindrical surface of the portion I6. A recess 2| occurs in the surface of f the shank I0 at the lower end of the portion I6 and is diametrically opposite the enlargement 20.

The cutter II is rotatably supported and retained on the shank portion I5 by the means I2 to have its longitudinal axis A inclined relative to the longitudinal axis B of the shank. In accordance with the invention the cutter II includes an annular or tubular body 22 surrounding the shank portion I6. 'Ihe longitudinal opening 23 in the'cutter body 22 is concentric with the longitudinal axis of the said body and has a cylindric wall. The diameter of the opening.

23 is somewhat greater. than that of the shank portion I6 for the purpose to be hereinafter described. While the cutter body 22 may be shaped as found most desirable it may have its external surface` substantially spherically curved as illustrated in the drawing.

The invention provides novel and improved teeth or cutting parts 24 on the cutter body 22. The cutting parts 24 project outwardly from the external surface ofthe cutter body 22 and in the case lillustrated are integrally joined with the body of the cutter. The cutting parts 24 are preferably independent of one another andarranged in rows. Therows of. cutting parts 24 are spaced circumferentially` one from the other and extend between the upper and lower ends of the cutter body 22. The rows of cutting parts v24 are pitched or inclined downwardly and forwardly relative to the direction of rotation of the reamer shank I0. The individual cutting parts 24 of the rows are offset or staggered vertically and circumferentially of the cutter body 22. The adjacent cutting parts 24 of the rows may be in close proximity to one another. In the particular case illustrated in the drawing the lower forward corner of a. cutting part 24 is immediately adjacent the upper rear corner of the adjoining or adjacent part 24. The outer surfaces 25 of the cutting parts 24 are inclined or curved downwardly and outwardly from theA cutter body 22. The lower ends or surfaces 26 of the cutting parts 24 may be at andY substantially normal to the axis A as shown in Figs. 1, 2, and 4. However, it may be preferred to curve the lower surfaces of the cutting parts upwardly and inwardly to the body of the cutter as shown at 26"L in Fig. 5. The outer surfaces 25 and the lower surfaces 26 join at cutting edges 21. The cutting teeth or parts 24 may be of downwardly increasing thickness. which face rearwardly relative to the direction of rotation of the reamer may be inclined downwardly and rearwardly as disclosed in the drawing.

It is an important feature of the invention that the cutting edges 21 of the several cutting parts 24 travel in a spherical plane or path or a path partially defining or bounding a sphere. The cutting parts 24 are formed and proportioned so that their edges 21 are equally spaced from a common point P in the central longltudinal axis A of the cutter I I. In practice the point P constituting the axis of the spherical path of movement of the cutting edges 21 occurs at or is coincident with the point of intersection of the For example, their ends lor sidesl axis A and B. Where the external surface of the cutter body 22 is not spherically curved about the point P the cutting parts. 24 may vary somewhat in size to have their cutting edges 21 equidistant from the point P. In other respects the plurality of cutting teeth 24 may be alike in size. The upper cutting'parts 24 occur at or adjacent the upper end ofthe cutter body 22, for example, they may project downwardly and outwardly from the upper end of the cutter body. The lowermost cutting parts -24 are preferably positioned so that their cutting edges 21 are in or adjacent the plane of the lower end of the cutter body 22. The action or operation of the cutter II and its cutting parts 24 will be hereinafter set forth in full in the description of operation of the reamer. A

The means I2 relates the cutter II andthe shank Ill .for relative rotation and provides or includes annular grooves 28 in the shank portion I6. The grooves 28 are partially circular or partially spherical in transverse cross section and are spaced from the upper and lower ends of the shank portion I6. Correspondingly shaped annular grooves 29 are provided in the wall of the opening 23 in the cutter body 22. 29 are spaced and positioned to directly oppose the grooves 28. Series of balls 30 are arranged in the two pairs or sets of grooves 28 and 29. The balls 30 support the cutter I I on the shank I0 and y cooperate with the grooves 28 and 29 to hold the cutter against longitudinal movement and displacement from the shank portion I6. The' parts are related so that the wall of the opening 23 is spaced a considerable distance from the surface of the shank portion I6 providing an annular space for holding lubricant. Openings 3I are provided inh the wall of the cutter body 22 to allow the balls 30 to be placed in the registering or opposing grooves 28 and 29. The openings 3l are normally'closed by plugs 32.

Means may be provided for sealing the opposite ends of lthe space between the wall of the cutter opening 23 and the surface of the shank portion I6 to retain the lubricant in the space and to prevent the accumulation therein of cuttings and solid matter. A packing or sealing assembly is provided in each end portion of the cutter opening 23. Each of said assemblies includes two split rings 33 and a continuous or unbroken packing ring 34 between the pair of rings 33. The packing rings 34 may be formed of rubber or the like and are adapted to seal with the wall of the opening. 23 and the surface of the Shank portion I6. The shoulder I 1 on the shank I 0 of course prevents displacement of the upper packing assembly. 'I'he two rows or series of balls 30 limit the inward movement of the packing assemblies. Means is provided for holding the lower packing assembly against downward displacement from between the cutter body 22 andthe shank p0rtion I5. A resilient snap ring 35 is sprung or pressed into a groove 36 in the wall of the opening 23 to cooperate with the wall of a groove 31 in the lower split'ring 33. The snap ring 35 effectively prevents loss or displacement of the lower packing assembly.

In operation the shank I0 is interposed or connected in the drilling string so that the reamer operates in the desired position or zone in the weil. As the drilling string is rotated and fedy -downwardly in the usual manner the cutting parts 24 act on or engage the formation at the side wall of the well bore. The cutter II being rotatably supported on the shank I 0, the engagetained in an inclined position with relation to the shank and when it lags or is held ag-ainst turning it is given a gyratory motion. In other words, during rotation of the drilling string any given point on the cutter II or any given cutting part 24 gyrates and the center or axis of this motion -is the pointv P. The cutting parts 24, are thus given both. horizontal and vertical movement with respect to the shank I0.

The rows of staggered teeth or cutting parts 244- are moved upwardly in a rotary manner and then moved downwardly in a similar manner with described the cutting kedges 21 successively cut.

into the wall of the well bore as they approach and reach the. line of intersection or joinder of the spherical path X and the wall of the bore. The cutting parts 24 are preferably proportioned so that one cutting part 24 of a row bites into the formation as a lower adjacent cutting part leaves or moves out of contact with the formation. The adjacent higher cutting part 24 is also advancing into. contact with the form-ation and in this manner each row-of cutting parts 24 has at least one of its number in active engagemen with the formation. f

The cutting parts 24 arranged in downwardly and forwardly inclined rows progressively move or swing across a given portion of the wall of the well bore and being staggered do not track in their action on the formation. Due to their configuration and their gyratory movement the cutting parts 24 bite or dig into the formation to effectively cut away the same. Because the cutting edges 21 of the cutting parts 24 move in the spherical path X a plurality of cutting parts 24 are in activecutting engagement with the wall of the well bore at circumferentially spaced points.v

' I I by the rotary motion of the shank Ill moves the row of cutting parts 24 rearwardly and upwardly until they again move downwardly and forwardly.

The digging action of the cutting parts 24 is particularly elcient in removing the formation at the side wall of the bore. The cutting edges 21 of the cutting parts travelling through the spherical path X engage the wall of the Well bore at spaced points throughout its circumferential extent as distinguished from disc-like-annular cutters, rotatable about axes inclined relative to a shank, which disc-like cutters can only have active engagement with the formation at diametrically opposite points. The reamer of the present invention is particularly steady and smooth in its operation because of the engagement of its cutting parts 24 with the wall of the bore at equally spaced points. 'I'he spaces between the rows of cutting parts 24 constitute channels for freely passing'the upwardly flowing circulation fluid in the well bore so that the cutter II does not materially obstruct the iiow through the well.

The anti-friction retaining means I2 is such that the engagement of the cutting parts 24 with the.

formation in most instances holds the cutter against turning with the shank so that the cutting 'parts have the desired gyratory motion and cutting action.

In assembling the ,cutter II on the shank I Il the body 22.o f Ithe cutter may be freely passedA over the lower portion of the shank until it Areaches a position where one side portion is receiv`ed in the recess 2I and the opposite side portion is at the enlargement 20. The cutter body 22 may be tipped relative to the shank I0 as it enters the recess 2l so that it may b'e swung or pivoted over .the spherically curved enlargement 2Il'to the inclined position where it surrounds the shank portion I6. It is believed that it will be clear howthe series of balls 30 may be arranged in the'grooves 28 and y29 and how the packing assemblies may be positioned in the op-f posite ends of the cutter opening 23. As the cutter I I may be readily passed over the end portion of the shank I0 to its position around the portion I6, the shank Il) may be a simple integral member as illustrated in the drawing.

Having described only a typical preferred form and application of my invention I do-not'wish to be limited or restricted to the specific form and application herein set forth, but wish to reserve to myself any modicationsor variations that may appear to those skilled in the art or fall within the scope of the following claims.

Having described my invention, I claim:

1. A well reamer including a shank adapted to be connected in a drilling string, a cutter surrounding and rotatably supported on the shank, and-.circumferentially and vertically spaced cutting parts on the cutter adapted to operate in` a path constituting a portion of a sphere and simultaneously contact the wall of the well 'bore at spaced points throughout its circumference.

2. A well reamer including a shank adapted to be connected in a drilling string, acuttersurrounding the shank and having an axis inclined with respect to vthe axis of rotation of the drilling `be connected in a drilling string, an annular y cutter surrounding the shank and yhaving a substantial longitudinal dimension relative to its diameter, circumferentially spaced rowsvof verti- .cally spaced teeth on the cutter,A and means'rotatably supporting the cutter on the shank with its axis inclined relative to the axis of rotation of the string whereby the cutter is operable -to simultaneously act on the wall of the well at diametrically opposite points. y

4. A well reamer including a shank having means at its opposite ends for connecting it in a drilling string, a cutter surrounding the shank and having its axis inclined relative to the axis of rotation of the drilling string, the shank and cutter being related for relative rotation, and circumferentially and vertically spaced cutting parts on the cutter operable to simultaneously act on the well bore at spaced points throughout its circumference.

5. A well reamer including a shank adapted to be connected in a drilling string, a cutter surrounding and rotatably arranged on the shank with its axis inclined relative to the axis of rotation of the drilling string, and circumferentially spaced inclined rows of cutting parts on the cutter having cutting edges which operate in a path constituting a circumferential portion of a sphere and simultaneously act on the wall of the 'well at spaced points throughout its circumference.

6. A well reamer including a lshank having means at itsopposite ends for` connecting 'it in a drilling string, a cutter surrounding and rotatably mounted on the shank with its axis inclined relative to the axis of rotation of the drilling string, and circumferentially and longitudinally staggered cutting parts on the cutter operable to 4simultaneously act on the wall of the Well atl spaced points throughout its circumference.

7. A well reamer including a shank, means on the opposite ends of the shank for connecting it in a drilling string, a cutter surrounding and rotatably arranged on the shank with its axis inclined relative to the axis of rotation of the drilling string, and circumferentially spaced rows of vertically spaced teeth on the cutter.

8. A well reamer including a shank, means at the opposite ends of the shank for connecting it in a drilling string, a cutter surrounding the shank and rotatably retained thereon to have its axis inclined relative to the axis of rotation of the drilling string, and circumferentially spaced rows of longitudinally and circumferentially staggered cutting parts on the cutter, the cutting parts of said rows being staggered circumferentially in a forward direction relative to the direction of rotation of the drilling string.

9. A well reamer including a shank having threads at its opposite ends whereby it is adapted to be interposed in a drilling string; said reamf er being characterized by a gyratory cutter surrounding the shank and including a plurality of rows of vertically and circumferentially offset teeth having cutting edges operating in a path forming a portion of a sphere whose center is in or adjacent the longitudinal axis of the shank.

` 10. A well reamer including a shank, means at the opposite ends of the shank for connecting it with a drilling string, a cutter surrounding and rotatably supported on the shank to have its longitudinal axis inclined with respect to the longitudinal axis of the shank, and circumA ferentially spaced rows of vertically and circumferentially staggered cutting parts on the cutter, the cutting parts having lower outer cutting edges operating in Va path constituting a circumferential portionof a sphere.

1l. A Well reamer including a shank, means at the opposite ends of the shank for connecting it with a drilling string, a cutter surrounding and rotatably supported by the shank to have its axis inclined with respect to the longitudinal axis of the shank, and projecting cutting parts on the cutter for .simultaneously acting on the wall of the Well at spaced points throughout its circumference, the cutting parts having downwardly and outwardly inclined upper sides and undercut lower sides joining at cutting edges operating in a path which constitutes a circum- `ferential portion of a sphere.

12. A Well reamer including a shank, mean at the opposite ends of the shank for connecting it with a drilling string, the shank having a portion whose longitudinal axis is inclined with respect to the longitudinal axis of the shank, a downwardly facing thrust shoulder at the upper end of said portion, and a cutter rotatable on said Athe body, an annular groove in said integral collar portion, an annular cutter member having an internal annular groove coinciding with the annular groove in the collar portion, and a se- CHARLES J. MAHER. 

